Adding Storage To An Already Full Bedroom?

Q: We've slowly acquired bedroom furniture that we love, but have not made the most practical choices in terms of dealing with the small amount of storage space we have. One teeny closet for two people. We have two danish dressers that can't handle sweaters and I bought a desk which is what i needed (but not what I wanted). So, I need to find creative ways to store things like sweaters, pajamas, gym clothes etc. I will have underbed boxes but don't want to always rely on them.

I've been thinking about adding an IKEA EXPEDIT right next to the closet but I'm concerned that will make the space look too crowded. Any suggestions?